THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

(COMMERCIAL BREAK)

ANNOUNCER: This is CNN breaking news.

ANDERSON COOPER, CNN HOST: I'm Anderson Cooper in Parkland, Florida. I want to welcome our viewers here in the United States and watching around the world.

A stunned and grieving community and possible warning signals that were missed. We're following up-to-the-minute developments in the Florida school massacre that left 17 people dead, at least 14 others wounded.

Here's what we know right now. The shooting suspect is due in court an hour from now. Police say he's a former student at the school.

A law enforcement official tells CNN the FBI received at least two alleged threat reports about the shooter, including a YouTube post. In both cases the FBI did not share the information with local law enforcement.

And President Trump steps into the role of comforter-in-chief. The president addressed the nation, pledging to make schools safer.

(BEGIN VIDEO CLIP)

DONALD TRUMP, PRESIDENT OF THE UNITED STATES: It is not enough to simply take actions that make us feel like we are making a difference. We must actually make that difference.

In times of tragedy, the bonds that sustain us are those of family, faith, community and country. These bonds are stronger than the forces of hatred and evil. And these bonds grow even stronger in the hours of our greatest need.

And so, always, but especially today, let us hold our loved ones close. Let us pray for healing and for peace. And let us come together, as one nation, to wipe away the tears and strive for a much better tomorrow.

(END VIDEO CLIP)

COOPER: We're learning new information by the hour. I want to bring in CNN Correspondent Brian Todd and CNN Justice Correspondent Evan Perez.

Evan, what more have you learned, at this point, about the threat reports the FBI received about this shooter?

EVAN PEREZ, CNN JUSTICE CORRESPONDENT: It was that report that was sent in to the FBI in 2017. This was a state -- this was a comment that was left on a YouTube video. And it said something to the effect of, "I'm going to be a professional school shooter."

The FBI says that they did look into it. They went and they spoke to the person who called in the report, who reported the threat. And they said that they looked -- they went through databases that the FBI has access to. But it appears that they never were able to identify this person.

Now, there's a lot of questions that are -- that are still outstanding for the FBI. Because, obviously, the statement -- the comment that was left on the YouTube channel was left in the name of this -- of this shooter, Nikolas Cruz.

So, the question that the FBI, I think, still has to try to figure out how to answer is why -- if this person is still using his name, why is it that they weren't able to figure out how to track him down?

And also, you know, there was, apparently, another incidence in which there was another threat that was -- that was told to the FBI that went back to this shooter. And, in that case as well, it appears the FBI was not able to really get to the point of launching a full investigation.

And there is a lot of perplexed people down there in south Florida who say, you know, the FBI should have passed this, perhaps, to the law enforcement there in local -- in the local jurisdiction which has a lot of resource and might be able to spend more time tracking this down.

COOPER: What do we know, Evan, at this point, about the accused shooter, how he got the weapon?

PEREZ: He purchased the AR-15-style rifle legally, Anderson. He purchased it almost about a year ago, just under a year ago from a gun store in a town right near Parkland, where this shooting took place. Everything appears to have been done normally. He passed the background check.

At his age, 19 years old, he is perfectly legally able to buy an AR- 15-style rifle. He's not old enough to buy a handgun, under federal law. But he is perfectly legally able to buy this AR-15-style rifle.

And according to the people we've talked to, the sources we've talked to, he passed the background check.

Because even though there appears to have been a lot of trouble in this young man's life and perhaps even mental health issues, none of that showed up in the background check. Because he was not yet adjudicated as mentally defective which is the standard that the federal law requires for you to be denied a gun sale.

COOPER: Brian, you're outside the courthouse where the suspect is due to appear next hour. Can you just walk us through what's going to happen at that hearing, what we expect?

[13:05:02] BRIAN TODD, CNN CORRESPONDENT: Right, Anderson. We're told, by the court officer, that his appearance, his first appearance, in court will be in less than an hour, at approximately 2:00 p.m. Eastern time. It may take only about three minutes.

The judge is expected to possibly appoint him a public defender, or at least an interim attorney, to represent him, at least on a temporary basis.

I spoke not long ago a prominent local attorney, Mark O'Mara, a defense attorney who has defended a lot of high-profile cases. I asked him to walk me through what could happen here.

He said, look, the judge is probably going to tell the defendant, Nikolas Cruz, that he has probable cause to hold him over for charges. This will likely not be an arraignment. That may be some weeks away, Anderson.

But he will hold him over for charges. He probably will not give him any bond. And he will tell him there is probable cause to believe a crime has been committed here. And he may ask him how he pleads but he may not ask him that.

Mark O'Mara told me that he -- the judge may try to limit the amount that Nikolas Cruz actually speaks in court. So, this will be a first appearance.

He will probably be told that he's got probable cause to hold him over for charges. That he probably will not get bond. And he may or may not ask him how he pleads, in this case, Anderson. We do know that he's been charged by police with 17 counts of premeditated murder.

COOPER: And, Brian, what do we know about the suspect's family history, his mental state?

TODD: We've been told, Anderson, by friends and others who knew this suspect, that his mother, his adoptive mother, died in November of pneumonia. That his father, his adoptive father, died several years ago.

And an attorney representing a family who took Nikolas Cruz in did speak to some reporters last night outside that family's residence. And said that the family is very distraught over this. That they had not expected anything like this.

They knew that he had weapons but they kept them under lock and key. They thought that would take care of it. They had no indications that they saw from him that he could commit a crime like this. And that they are very distraught.

Now, the mayor of Broward County has said that he underwent some treatment for medical -- for mental issues, excuse me. But the mayor would not go into specifics about those.

We did hear a lot of references, in the news conference this afternoon, Anderson, from the sheriff and from others, about the need to treat people with mental health issues.

So, there are indications that we're getting that he might have had some mental health issues, but officials haven't really drilled down on that yet.

COOPER: All right, Brian Todd, I appreciate it. Evan Perez as well.

More than a dozen people were injured in the shooting and taken to hospitals. Seven of those remain. They're still there. Many in critical condition, fighting for their lives.

Here with me now is Dr. Christopher Roberts with Broward Health Medical Center. Thanks so much for being with us. You've had a very, obviously, horrific 24 hours or so. Can you just take us through the condition of those who are still in the hospital?

DR. CHRISTOPHER ROBERTS, BROWARD HEALTH MEDICAL CENTER: Well, we still have a couple critically injured at north -- at our north hospital, sister hospital, Broward Health North. One has been downgraded so that's good news. And everyone is fairly stable at our hospital, Broward Health Medical Center.

COOPER: You were -- were you involved in the triage last night?

ROBERTS: I was. I was there just -- I'm the chief of neurosurgery, so I take care of brain and spinal cord injuries. And, fortunately, we did not see any at our hospital.

COOPER: You had also been involved in the past shooting, I believe, at the Ft. Lauderdale Airport.

ROBERTS: Yes.

COOPER: So, you've seen these kind of wounds before?

ROBERTS: Correct. Penetrating trauma. It's something that we train for day in and day out.

COOPER: When you get a call like this, I mean, how does -- how does the team kick into place? How does it actually mobilize?

ROBERTS: It is certainly controlled chaos. But it's something that we plan for. We deal with trauma letters almost on a nightly basis.

On a mass casualty situation, you don't really have time to weigh the gravity of that situation, at the time, because that'll affect patient care.

COOPER: So, in a sense, you have to, kind of, put the real -- the gravity of it out of your mind, as a human being?

ROBERTS: Absolutely. COOPER: And that -- I mean, I assume that comes later.

ROBERTS: It does. It does. It does when you go home and maybe think about things, maybe watch the news and find out the gravity of the situation.

But when you have patients that are critically injured that need your help, you can't be focused on what happened at that time. You need to focus on treating that injury.

COOPER: And the wound -- the kind of wounds that you saw yesterday, I assume most of them gunshot or fragments at the threat?

ROBERTS: Correct.

COOPER: And do you have any sense of how long the others are going to be in the hospital for?

ROBERTS: It's hard to tell. It's -- you know, it's a very individualized basis on how they progress with physical therapy, and et cetera.

COOPER: Well, Dr. Roberts, I appreciate all your efforts of you and all the doctors and nurses. Thank you so much.

ROBERTS: OK.

COOPER: Appreciate it.

The city of Parkland, Florida is, obviously, a small, tight-knit community. Today, those bonds are being tested in the aftermath of the shooting at the Marjory Stoneman Douglas High School. Seventeen people murdered, lost their lives.

[13:10:00] Many lawmakers, members of the Trump administration, have said that they will keep the families of the victims in their thoughts and prayers.

Here's what President Trump said a short time ago.

(BEGIN VIDEO CLIP)

DONALD TRUMP, PRESIDENT OF THE UNITED STATES: Our entire nation with one heavy heart is praying for the victims and their families. To every parent, teacher and child who is hurting so badly, we are here for you, whatever you need, whatever we can do to ease your pain.

(END VIDEO CLIP)

COOPER: I'm joined by the mayor of Parkland, Christine Hunschofsky. Thank you so much for being with us in this incredibly difficult time. You never imagined you would be standing here on this day in this kind of a situation.

CHRISTINE HUNSCHOFSKY, MAYOR, PARKLAND, FLORIDA: Never. Parkland is a small city in northwest Broward County. A little over 31,000 residents. Very close-knit, very family-oriented.

We moved here almost 18 years ago. Raised our boys here. And you would never imagine something like this could happen here.

COOPER: When you got the call yesterday, I mean, as the mayor, what do you do?

HUNSCHOFSKY: So, I first got the call that they were on the scene. They had an active shooter call. So, I thought, well, maybe it's one of those pranks. You have those pranks sometimes. And then, I heard all the sirens driving by. I live right nearby. And then, I knew it was something more than, you know, just somebody calling something in.

I came to the scene immediately just as they were setting up the perimeter. Parents were slowly arriving. And it's heartbreaking to watch parents when they haven't heard from their children yet.

Thank god for technology that allowed children to text their parents and let them know they were OK. But the shooter, in the beginning, hadn't been apprehended yet so there was a lot of nervousness.

And then, the police were wonderful about going section by section in the school and making sure it was safe. And as soon as they could get the kids out, they did.

And to see parents hugging their children that they weren't sure they were going to see again was -- I don't even know words to describe it.

COOPER: Yes. Of course, 17 families did not have that joyful reunion.

HUNSCHOFSKY: Yes.

COOPER: And others are still now in the hospital. I know your thoughts are with all those who lost their lives --

HUNSCHOFSKY: Yes.

COOPER: -- and all those whose lives are forever changed.

HUNSCHOFSKY: We have such a small, close-knit community between our soccer leagues and our sports leagues and our PTAs and just the volunteer mindedness in our community. Most people know someone who was affected tragically by this.

And it's -- I hope we're going to keep focusing on them. As a mayor and as our city, we're making sure that they have the support and the services they need in this time. That's very important to us.

COOPER: You know, you heard what the president said. I mean, what does this -- what will change? I mean, can anything actually change?

HUNSCHOFSKY: I sure hope so. And I think anybody who goes into public service today has to have some sense of optimism about them that there is hope that something can change. I think -- I don't know what number is best this year (ph). I'm hoping people are become more aware, people more aware that they see something, that say something about it. Talking to each other a little more. I don't know how it changes. And I'm sure we'll have better ideas a week or so from now.

But I hope we really start talking about these things. It seems like we all want to take a side on something, as opposed to rolling up our sleeves and doing the hard work of coming up with a solution. Because if it were that easy, I think we would have had one already.

COOPER: Well, Mayor, I appreciate your time. Thank you very much. I wish you the best.

HUNSCHOFSKY: Thank you very much.

COOPER: Thoughts and prayers but no real change. How inaction in Washington has, really, become the normalcy for the Republican Senator Mike Rounds on why that is and will anything change this time next.

(BEGIN VIDEO CLIP)

STEVE KERR, COACH, GOLDEN STATE WARRIORS: It doesn't seem right to our government that children are being shot to death day after day in schools. It's not enough, apparently, to move our leadership, our government, people who are running this country to actually do anything. That's demoralizing.

(END VIDEO CLIP)

[13:14:25]

(COMMERCIAL BREAK)

[13:18:30] COOPER: Seventeen people from a high school in Florida have been killed. The community, the country, are coming to grips with yet another tragedy. A short time ago we heard from President Trump making his first public on-camera statement about the shooting. Here's what he said.

(BEGIN VIDEO CLIP)

DONALD TRUMP, PRESIDENT OF THE UNITED STATES: We are committed to working with state and local leaders to help secure our schools and tackle the difficult issue of mental health. Later this month, I will be meeting with the nation's governors and attorney generals where making our schools and our children safer will be our top priority. It is not enough to simply take actions that make us feel like we are making a difference, we must actually make that difference.

In times of tragedy, the bonds that sustain us are those of family, faith, community and country. These bonds are stronger than the forces of hatred and evil, and these bonds grow even stronger in the hours of our greatest need.

(END VIDEO CLIP) COOPER: We invited Republican Senators Marco Rubio and Ted Cruz and Florida's Republican governor, Rick Scott, to come on the show. They declined. They've been on Fox News, where they won't be pressed, perhaps, about gun control.

But we're very pleased, joining me now from Capitol Hill, Senator Mike Rounds, Republican from South Dakota.

Senator, thanks so much for being on.

First of all, you heard the president. I wondering what you thought of his message and do you think -- what kind of a difference do you think he's specifically calling for?

[13:20:07] SEN. MIKE ROUNDS (R), SOUTH DAKOTA: Let me first of all say that I echo what the president said. Our hearts and our prayers are with the folks in Florida. Our prayers go out to the families and to the individuals who are fighting for their lives right now. I think the president set the right tone, and I was very pleased to hear him suggest that it was important that he work with governors and attorneys general to move forward.

I think that we should be, as I would say, putting in additional defensive capabilities, a series of defenses within the -- the united -- or within the different school systems. And I think at the federal level, we have an obligation to step in and to work with those governors, our local units of government, to try to see that happen.

I know schools have tried. I know that they've done a lot of it. But the reality is that we could do more, I believe, by making a series of defenses.

COOPER: When you -- when you talk about defensive, you know, greater defenses within schools, what specifically do you mean?

ROUNDS: Yes. Let me give you an example. This morning I walked into an office building in downtown Washington, D.C. When I walked up to the front door, the door was locked. I had -- there was a television camera there. They looked at me. Identified ourselves. We walked into the next set of doors. Another person came, looked at me and then opened up the second set of locked doors. I then went to a desk where a person wanted to see my identification. Once I provided my identification to them, they then gave me an ID card and then another person came in and opened the door and allowed me to walk into an office building.

Think about what would happen if at the school systems we had experts, professionals, actually laying out a series of defenses. In other words, a series of layers in which we could actually provide additional protection for young people.

They're the most valuable asset we've got. And I think there is a real opportunity here to talk with professionals about what types of layers could be provided across this country.

COOPER: You know, a number of schools do have, you know, metal detectors, they have guards. This school had an armed guard as well who actually did not encounter the shooter.

I want to play some of the comments today from the Broward County Sheriff and just have you respond.

(BEGIN VIDEO CLIP)

SHERIFF SCOTT ISRAEL, BROWARD COUNTY, FLORIDA: What I'm asking our lawmakers to do are to go back to places like Tallahassee, places like Washington, D.C., and give police the power, if they see something on social media, if they see graphic pictures of rifles and blood and gore and guns and bombs, if they see something, horrific language, if they see a person talking about, I want to grow up to be a serial killer, we need to have the power to take that person and bring them before mental health professionals at that particular time involuntarily and have them examined. People are going to be rightly so concerned about their rights, as am I. But what about the rights of these students? What about the rights of young kids who go to schools with bookbags and pencils? Don't they have the right to be protected by the United States government to the best of our ability?

(END VIDEO CLIP)

COOPER: He also called for commonsense gun laws, in his words. What about that? I mean that seems to be, obviously, one of that a lot of politicians just stay away from, changing any gun laws.

ROUNDS: Well, let me answer --

COOPER: Are there any gun laws that you would be willing to change?

ROUNDS: Let me identify two things. First of all, let me talk about what he suggested with regard to having access to social media.

I think he has hit it on the head in terms of being able to do the advance work. And I think technology could be used to identify those areas in which these types of activities are actually going on. Right now when we talk about what the Russians are doing here, we can also talk about one -- about what young men and women are doing here as well if we're willing to provide that opportunity to law enforcement to actually go in and to look for those types of warning signs in advance. So I agree with him, I think that would be a step in the right direction. And I think the technology could be identified that we could work with.

Now, with regard to the other issues, I know every time one of these happens, and it happens way too often, there's always a discussion, some folks immediately, some others later on down the road, when they talk about gun control, they immediately talk about what they could do with regard to those guns that are in the hands of law-abiding citizens. The challenges is, is to get the guns out of the hands of those people who do us harm. Society has a responsibility to protect us from those who would do us harm.

And I still think, Anderson, and I know there's people out there that would disagree, what we have to do is to identify those individuals who would do us harm. And that means if they're -- if they're adjudicated as being mentally ill, the way the laws are today, then they shouldn't be able to have that gun. I think the challenge is getting to the point where we can identify those individuals who truly cannot be allowed to have a gun in the United States.

COOPER: This 19-year-old legally purchased this because there weren't any records on him, he had not committed a crime, so he -- I mean he got this AR-15-like weapon legally.

[13:25:10] You know, there have been a number of specific measures proposed. After Las Vegas, a lot of people talked about some sort of a ban on bump stocks, like the ones used in Las Vegas. A ban on high- capacity magazines that could allow as many as 30 shots to be fired before reloading, suggesting the federal age restriction for assault weapon ownership you raise from 18 to at least 21. You have to be 21 to get a handgun, but you can get an AR-15 when you're 18.

Would you be willing to have any movement on those things, bump stocks, high-capacity magazines, raising the age of getting an assault weapon?

ROUNDS: Yes. In fact, I've -- with specific -- with regard to bump stocks, I'm already on record saying, look, that turns a gun from a semi-automatic basically into an automatic weapon. We have law on the books right now that say that you can't have an automatic weapon without having a specific license, going through additional work. I agree with that. I think that's a step in the right direction.

But then you start talking about trying to identify a particular type of weapon or long gun that someone should not be able to have. The challenge is to identify any weapon that is then, by adjective, calling it assault, would suddenly be subject to additional work.

Look, I think back about the types of guns you're talking about. In this particular case, you're suggesting a 30-round clip. I've seen smaller clips that you can simply take two smaller clips, tape them together, and they do the same thing. So it's not so much the size of that clip as much as trying to get that individual who has that interest in the first place, to try to get ahold of that person before damage can be done and recognizing -- and I think here the law enforcement officers down there spoke with a great deal of integrity and thought, and that is, is young people share on social media what they're thinking about.

And, in many cases, it's a sense of reaching out and telling other people. It's almost like they're suggesting to people that they need help. I'm not sure, but I think those folks that have an interest in the personal side of protection and privacy, I even think those folks agree with this, that there has to be a way to identify those folks so that we can find out where those problems are before they actually take action.

COOPER: Yes, I mean, a lot of politicians say, let's, you know, listen to law enforcement on this, and that's one of the things you were just saying. But most law enforcement are actually in favor of some change in what they refer to as commonsense gone laws. I mean does a hunter need a 30-round magazine? ROUNDS: I think the question is, is at what point do you change it? Is

it 10 rounds? Is it 15 rounds? I've got a gun myself personally that was made in the late 1940s that actually you could put 21 rounds in and it's a Winchester Model 61. And it's a -- it was designed for target practice and rabbits. But to suggest that those types of things, simply because they have a magazine that's been built into them that we've had for years somehow would then be identified as an assault weapon, I think that's where you start running into the problems.

And part of the problem we have, Anderson, is that because of a very emotional issue at that point where once you start saying this is an assault gun because it has a larger magazine, or this is an assault gun because you can have it as a semi-automatic. I've got a three-shot automatic shotgun. Under some proposals, that suggests it's a semi- automatic that it also defines itself as an assault weapon. Even though it's not a rifle, it could be used. And I think that's where a lot of those of us who actively have learned how to properly and safely use firearms over the years, that's where we get really nervous about who's defining what those are and at what point does that become a license to simply eliminate the opportunity for the exercise of the Second Amendment rights? And I think we have to take some of the emotion away from it --

COOPER: Yes, and I -- I get that and I --

ROUNDS: Yes.

COOPER: Yes.

And I certainly respect hunters and, you know, land that people hunt on and I think it's great. It's part of the amazing thing about America.

But I just don't understand how anybody could say that a high capacity magazine, whether it's 30 rounds or 40 rounds or whatever it is doesn't help somebody who walks into a school to just kill more people? I mean the ability to kill large numbers of people in a very short period of time is certainly aided by these high-capacity magazines, no?

ROUNDS: I can show you examples, though, where we talk about we say common sense approaches. I can show you where you can take two clips, tape them side by side, flip them from one to the other as quick as anybody can, and you can go from 15 rounds to 30 rounds just by a piece of tape. So then what do you say? Is it going to be five and five and five?

I think -- I think the issue really is, you know, people are taking about the high-capacity of a magazine. They simply have more magazines. It still comes back to that mindset of somebody wanting to do harm to someone else. And I think if we focus on only the size of the cartridges --

COOPER: It does -- it does require a slight --

ROUNDS: Yes, no, I understand what you're saying.

COOPER: It does require, though, a slight pause in shooting to reload and maybe the person fumble -- I'm just saying --

ROUNDS: Yes.

[13:30:03] COOPER: I mean is there no limit to -- to how -- how many bullets somebody should be able to fire in one go, in one magazine?